This presentation provides an overview of the nuclear accidents that occurred at the Fukushima I power plant on March 11, 2011.

1. Fukushima Dai-ichiNuclear Power Station Accident by Joseph S. Miller EDA, Inc presented at ASME Energy Committee Colloquium May 10, 2011 Brigham Young University

2. Introduction Over 35 Years in the Nuclear Power Industry MS Nuclear, BS Mechanical, BS Industrial Worked at a BWR Nuclear Power Station for 9 years. Responsible for fuel, safety analyses and PRA. Responsible for the Nuclear Steam Supply Systems Technical Support Manager for Emergency Response Organization. Supported the Nuclear Regulatory Commission (NRC) in reviewing Nuclear Power Plant Safety Systems.

3. Acknowledgement for Use of their Reference Material Thanks to Japanese Industrial Atomic Forum (JIAF) Tokyo Electric Power Company (TEPCO) AREVA PowerPoint- The Fukushima Daiichi Incident – Dr. Matthias Braun Nuclear and Industrial Safety Agency (NISA) & Japan Nuclear Energy Safety Organization (JNES) on Plant Data Lake H. Barrett- Foundation For Nuclear Studies Briefing General Electric VGB Power Tech

4. The Fukushima DaiichiAccident Plant Designs (Covered by Tom Hafera) What Happened? Accident Progression Spent fuel pools Radiological releases Impact on US

5. PWR – Pressurized Water Reactor

9. Nuclear Chain Reaction

11. What Happened?

17. The Real Catastrophe was from the Tsunami 26,000 (dead &missing) & 130,000 homeless (April 28, 2011) Lead four plants at Fukushima I to fuel damage and large releases of radiation

19. Tsunami Size Was Accident Cause 3/11 15:45 at Fukushima I

20. The tsunami hits Fukushima I

24. Plant Designs - Fukushima Dai-Ichi BWR is a Boiling Water Reactor Unit 1 is BWR/3 Units 2-4 are BWR/4 There are 56 Reactors in Japan (1-FBR, 4-ABWR, 29-BWR, 23-PWR) compared to 104 Reactors in the USA (35 BWRs & 69 PWRs) The Fukushima I reactors began operation in the 1970’s so they are all thirty - forty years old. Fukushima I Units 1-4 all are early vintage Mark I Containment Designs

26. All AC power to the station was lost when the tsunami flooded the EDGs, which occurred about 1 hour after the earthquake.

27. At that point, the plant experienced a complete blackout (no AC electric power at all). Commonly called a “Station Blackout”.

29. Containment Isolation

30. The Tsunami Hits

31. Decay Heat

32. Typical ECCS for BWR/3 & /4

34. Boiling began in the suppression pool and the drywell pressure began to increased in about 11 hours after the SBO.

35. In about 16 hours the water level in the core began to decrease and core degradation occurred (through some combination of zirconium oxidation and clad failure).

36. Venting occurred at about 23 hours after SBO and the hydrogen explosion occurred in the RB about 1 hour later.

38. Tank is 55 feet long, 12 feet in diameter

39. 26,000 gallon tank

40. Make-up to IC tank is from CST via AC pumps

44. The RCIC turbine drives a pump using make-up water from the wet well or CST

45. High Pressure Coolant Injection (HPCI) wasn’t used or did not work for Unit 2

46. DC power from batteries and/or the use of DC powered pumps were lost after 70 hours, which is phenomenal considering that they are only designed to last 8 hours.

47. Although sea water was injected within an hour after the loss of RCIC, it appears that water level continued to decrease in the RV and DW pressure increased. Significant pressure increases were observed in the RV.

48. No venting of the DW was observed

49. DW pressure stayed high on 3/15 00:00 and an explosion was heard in the lower part of the reactor building.

51. Isolation Condenser (Unit 1) and RCIC (Units 2 & 3) Were Used to Cool the Plants

52. Unit 2 Primary Containment Pressure (D/W) & Reactor Pressure (3/11 – 3/17)

54. DC power from batteries and/or use of DC powered pumps were lost after 35 hours (half the time when using only RCIC system for Unit 2), which is great considering that they are only designed to last 8 hours.

55. Sea water was injected within 6 hours after the loss of RCIC & HPCI, and it appears that water level continued to decrease in the RV and DW pressure increased. Core damaged was assumed to occur during this time period.

56. Venting of the DW was observed at 43 hours and at 64 hours after SBO.

58. Unit 3 Primary Containment Pressure (D/W) & Reactor Pressure (3/11 – 3/17)

60. Units 1, 2 & 3 Water Level

61. Units 1, 2 & 3 Reactor Pressure

62. Units 1, 2 & 3 Drywell Pressure

64. 3/14 13:25 in Unit 2

65. 3/13 2:46 in Unit 3

66. Decay Heat Causes the water to boil in the reactor Vessel and the pressure rises in the Reactor Vessel.

67. The steam is released into the wet-wet through the SRVs

69. Zr-Water Begins at

70. Release of Fission Products

71. Containment is Last Barrier

72. Venting the Containment

73. Hydrogen Explosion Units 1 & 3

76. Damage to Torus Unit 2

78. Radiation Levels

80. Fukushima I Fuel Pools

81. Fukushima Dai-ichi Site Reactor and Fuel Specifications

91. Fukushima Observations Not a Public Heath Catastrophe Inconsequential to Earth/Tsunami Impacts The Fukushima event rating was provisionally increased from level 5 to level 7 by Japanese officials on April 12, due to computer analyses indicating total discharged iodine-131 and caesium-137 in the early days of the event were sufficient to warrant an increased rating level. This rating increase did not reflect any new event. The radioactive release from Fukushima is very roughly estimated by Japanese officials to be about 10 percent of that released from the Chernobyl accident – with very important differences.

92. Fukushima Observations Not a Public Heath Catastrophe The most important difference between Chernobyl and Fukushima is no deaths or illness among the public are expected from the Fukushima incident. The Chernobyl accident emitted radioactive particles high into the atmosphere, which spread downwind across Europe, and a reactor fire continued this process for at least 10 days. Radiation from the Fukushima incident is mostly in the form of liquid runoff into the ocean and low-altitude particles that have frequently blown out into the ocean. At Fukushima, the reactor fuel remains inside the primary containment structures, whereas the Soviet Chernobyl design did not have a containment structure.

93. Fukushima Observations What is the risk of radioactivity getting into the US food supply? Normally very little food from the Fukushima region is imported into the USA. Affected foods from the region around the Fukushima plant have been banned from export by the Government of Japan. Any food from that area not already restricted by the Government of Japan will be detained for testing by the U.S. Food and Drug Administration (FDA) and not allowed into the USA unless shown to be absolutely free of contamination.

94. Three Mile Island History Reactor Scram: 04:00 3/28/79 Core melt and relocation: ~ 05:00 –07:30 3/28/79 Hydrogen Deflagration: 13:00 3/28/79 Recirculation Cooling: Late 3/28/79 Phased Water Processing: 1979‐1993 Containment Entry: July 1980 Reactor Head removed and core melt found: July 1984 Start Defuel: October 1985 Shipping Spent Fuel: 1988‐1990 Finish Defuel: Jan 1990 Evaporate ~2M gallons Processed Water: 1991‐93 Cost: ~$1 Billion

95. Impact on US Reactors US has implemented B.5.b requirements in 2008 Beyond Severe Accident Guidelines Onsite high pressure portable pump Procedures and appropriate staging areas and requirements for fire hoses and equipment on site MOUs with fire local fire stations to establish the plant as a priority in case of an emergency.

96. Impact on US Reactor Some of the things that should be reviewed Review all external events, i.e., fire, flooding, explosions and earthquake, to ensure that there is backup emergency equipment that can support a station black out. Review training for extreme station Blackout events and procedure. Ensure that emergency batteries are qualified for worst case events for fl0od, fire, explosions and seismic. The portable high pressure pump and associated equipment that was required because of B.5.b should be housed in a structure that is qualified for worst case fire, flood, explosion and seismic events.